Crash Tests: Small Cars Getting Safer, Still Vulnerable

by David Tenenbaum

In November, the Insurance Institute for Highway Safety (IIHS), Arlington, Va., released the list of top crash-test performers for 2010. Five small cars were named 2010 IIHS Top Safety Picks by meeting the tough criteria for good performance in front, side, rollover, and rear impact crashes, according to Joe Nolan, IIHS senior vice president.

"Compared to a few years ago, small cars have improved significantly. Every small car we've tested has side air bags as standard equipment," and an increasing number have electronic stability control, which greatly reduces the danger of deadly rollovers.

The five small cars that earned the Top Safety Pick are the Honda Civic, Kia Soul, Nissan Cube, Subaru Impreza, and Volkswagen Golf.

Ratings and results

For the first time vehicles have to meet a new rollover protection requirement to earn the top IIHS safety rating. The test measures roof strength by pressing a metal plate against one side of the roof at a constant speed. To earn a good rating for rollover protection, the roof must withstand a force of four times the vehicle's weight. "With the addition of the new roof strength evaluation, our crash test results now cover all four of the most common kinds of crashes," Nolan says. "Cars that earn the Top Safety Pick award are designs that go far beyond minimum federal safety standards."

Frontal crash protection has improved markedly in recent years, and Nolan says the same thing is now happening with side impact crash protection. Among the 33 small, mini, and microcars the IIHS has tested, 20 earn the highest rating of good in the side test. "This is a huge improvement from our first comprehensive round of small car crashworthiness evaluations in 2005 ," Nolan says. "Then, none of the 16 tested earned a good rating in the side evaluation. Most earned a poor rating."

When you go small, you're giving up some level of safety.

Rear-end crashes usually aren't fatal, but they result in a large proportion of crash injuries. Automakers have been focusing on preventing neck sprain or strain in these impacts by redesigning seats and head restraints. "A rear impact seems like it should be easy, and once you figure it out for one product, you could use that seat design for another car. We are seeing gradual improvements in rear crash protection."

The crash tests are violent. In the frontal test, for example, the car strikes a barrier at 40 mph. Some car makers have questioned whether the tests mimic reality on the road, but Nolan says, "Manufacturers say the tests are more severe than 98% of crashes. That's true, but a lot of those are fender-benders. About 30,000 vehicle occupants die in crashes each year, mostly in severe crashes, so the tests have got to be at the severe end of the spectrum."

To improve its testing, IIHS visits junkyards to see the results of real-world crashes. For years, the U.S. government's front-impact tests struck the auto against a flat wall, but "very few cars in the junkyards looked like they had hit a flat wall," Nolan says. "More often, we saw offset damage, where half of the car had taken the impact, so we changed our front-impact test." Designing for offset impacts "was a huge paradigm shift for the auto industry."

One response to the side-impact tests has been the widespread introduction of side air bags.

IIHS groups its results by auto size, since most buyers already have an idea of what general size of car they want. "People will choose for reasons other than safety, but within categories, we give the ability to compare cars," says Nolan. "If two vehicles will meet your function, and one performs really well on the tests and the other doesn't, that's an easy decision to make."

Larger is safer, usually

Both crash tests and on-the-road statistics show that large sedans are safest. But even though heavier, higher vehicles have inherent advantages in crashes, two big pickups—the Dodge Ram 1500 and the Nissan Titan—scored marginal in IIHS side-impact tests.

Tall, heavy vehicles also endanger other vehicles: Accident statistics show that when they hit a small car in the side, the higher front ends can cause serious head injuries, a finding that induced the Institute to raise the location of its side-impact tests several years ago. "We are trying to accurately represent the dangers out there to the fleet," says Nolan. "Our approach is, 'Let's look at the field data and see what tests we can derive to test that, and hope those tests can drive the market in the direction of safety.' "

One response to the side-impact tests has been the widespread introduction of side air bags, Nolan adds.

High bumpers on pickups and SUVs have reversed a long trend toward vehicle compatibility. For decades, the federal government has required that bumpers on most cars be 16 inches to 20 inches off the ground—so the bumper will strike heavy, protective structures in the car.

Both crash tests and on-the-road statistics show that large sedans are safest.

Because SUVs and pickups are exempt from the requirement, in July 2009 IIHS petitioned the federal government to regulate light-truck bumpers. "If the bumper is lower, you have a better chance of hitting something that will crumple and absorb energy," Nolan says.

Although small cars are improving, he says, "there's no doubt that small cars offer less safety than large cars, everything else being equal. You can't avoid the fact that if you are in a small car and are hit by a larger vehicle, you will be worse off. So it's a trade-off. When you want to go small for fuel economy or other reasons, you are giving up some level of safety. Size will matter even more now with increased restrictions due to the Obama Administration's fuel-economy and emissions initiative.

Our message is to be realistic. If you are downsizing for fuel economy, maybe you can get a midsize vehicle with a small 4-cylinder engine that gets close to the fuel economy of a small car.

Ratings winners

The latest crash test results, released November 2009, gave top safety ratings to five 2010 small cars:

Honda Civic

Kia Soul

Nissan Cube

Subaru Impreza

Volkswagon Golf

All have standard side airbags and electronic stability control at least as an option.